Thread-cutting device for sewing-machines.



R. L. LYON S. THREAD CUTTING DEVICE FOR SEWING MACHINES.

APPLIOATION FILED DEO.23.1907.

Patented June 14, 1910.

UNITED STATES ROBERT L. LYONS.

OF BOSTON, MASSACHUSETTS.

THREAD-CUTTING- DEVICE FOR SEWING-MACHINES.

To all whom it may concern:

Be it known that I, Ronnnr L. LYoNs, of Boston, in the county of Suffolk and State of h/Iassachusetts, have invented certain new and useful Improvements in Thread-Cut ting Devices for Sewin -Machincs; and I hereby declare that the I erence being had to the accompanying drawings, forming part of this specification:

This invention relates to improvements in thread cutting devices for sewing machines and particularly to improvements in such devices for cuttln the shuttle thread.

The object of tie invention is to so construct a sewing machine having a thread cutter that the undue drawing out of the under thread may be prevented.

Another object of the invention is to lock the shuttle bobbin from movement.

The invention consists in the combination with .asewing machine having a cutter against which the shuttle thread may be drawn, to out said thread, of means for limitin the drawing out of the shuttle thread.

T e invention consists in such other novel features of construction and combination of parts as shall hereinafter be more fully described and pointed out in the claims.

Figure 1, represents an end view of a sewing machine, partially in section, illustrating this improvement. Fig.2, represents a sectional view of parts of the same taken on line 2-2 Fig. 1. Fig. 3, represents a sectional detail view of parts thereof. Fig. 4, represents diagrammatically, the straining of the shuttle thread over the edge of the cutter.

. Similar numbers of reference designate corresponding parts throughout.

As shown in the drawings in its preferred form 5 indicates the head of any well known sewing machine having the bed plate (5 :t'urnished with the throat plate 7 having the needle hole 8 and the slot 9 extending from said needle hole and supplied with the cutter 10. In bearings of the bedplate 6 is journaled the shaft 11 of the shuttle carrier 12 furnished with the bobbin 13 and designed to be driven in any usual manner. In said shaft 11 is formed a longitudinal bore, located eccentric of the axis of said shaft, in which is slidably mounted the spring' retracted rod 14 hearing at one end against a portion of the bobbin 13 and at the other end against the presser plate 15 adjustably Specification of Letters Patent. Application filed December 23, 1907 Serial No. 407,618.

ollowing is a full, l r 1 clear, and exact description of the same, ret- Patented June 11, 19.10.

11101 rited on the cam arm 16 which is pivota y mounted on the bracket 17, extending from a part of the bed plate, and is furnisli'ed with the cam 18.

Pivotally mounted on the' head 5 is the le' ver19 which is pivotally connected with the usual presser foot lifter rod 20, slidably mounted in the head 5 and connected with tlie presser which, in the machine shown herein, is the button clamp 21. s

' Mounted to slide in a perforation formed in the bed/plate 6 is the rod 22 which has at its lower/ end the cam 23, hearing against the camend 18 of the arm 17, and pivotally connected at its upper end with the lever 19. On this rod 22 is the stop 24 against which the spring 25 acts to retract the rod 22 when said rod is relieved from the downward pres sure of the lever 19.

After the completion of the sewing operation the outer end of the lever 19 is depressed in any usual manner to raise the presser .foot. This movement of the, lever 19 depresses the cam 23 which acts against the cam end 18 of the arm 16 to swing said arm and press inward the rod 14 against the action of its spring whereby the inner end of said rod engages the bobbin 13 and prevents the rotation of the bobbin and the paying out of the thread thereon. When new 'the work A is drawn outward the thread B is drawn through the slot 9 ofthe throat plate 7 and becomes tight as the length of the slackthread is reached until this thread is drawn against the cutter 10, as shown in Fig. i of the drawing when the tightened thread is cut by said cutter.

This invention is not necessarily lint to the particular bobbin. her in an to the specific means for restraining the draw ing out of the thread fromthe bobbin for it is apparent that the object of the invention may be accomplished by any means which will resist the movement of the bobbin thread so that such thread may be tightened.

Having thus described my invention I claim as new and desire to secure by Letters Patent.

1. A sewing machine com rising a rotatable bobbin, slidable means f dr en aging the bobbin to prevent its rotation, the presser foot actuating lever, and means operated by the movement of said lever for movin said slid-able means into engagement wit the bobbin.

2. In a sewing machine the combination with the bobbin shaft rotatably mounted movement of the bobbin, resser foot operand having a longitudinal bore, the bobbin ating means, and means or actuatin said on said shaft, and a sprin retracted bobbin restraining means simultaneously wit the enga ing rod slidable in t c said bore of 'the operation of the presser foot operating bobbin shaft, of the presser foot actuator means.

and means operated by the movement of 5. A sewing machine comprising a throat saidactuator for moving said bobbin enplate having. a needle hole and a slot ex-- gaging rod-into enga ement with the bobtending from said needle hole, a button in, for the purpose; escribed. clamp for holding a button above said 3. A sewing machine comprising a bobbin needle hole, a bobbin movably mounted'bevmovably mounted, means for restraining the low said needle hole, and operative means movement of the bobbin to prevent the payfor positively holding said bobbin whereby ing out of thread, presser foot actuating the drawn forward ofthe work effects the means, and mechanism operated by or straining o the bobbin thread.

7 through saidpresser foot actuated means for ROBERT L. LYONS.

- operating said restraining means. Witnesses:

4. A sewing machine comprising a bobbin H. J. MILLER,

movably mounted, means for restraining the p M. M. HARRINGTON. 

